JP2015134865A - Primer composition and laminate prepared using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a primer composition having excellent adhesion to a base material and having excellent dispersion stability and a laminate obtained using the same.SOLUTION: A primer composition comprises a powder (X) comprising a reactive fluorine-containing polymer, a powder (Y) comprising an adhesive resin, and a fluorine-containing dispersion medium (Z) with a boiling point of 50-200°C. Based on 100 pts.mass of the powder (X) comprising a reactive fluorine-containing polymer, the content of the powder (Y) comprising an adhesive resin is 1-30 pts.mass and the content of the fluorine-containing dispersion medium (Z) with a boiling point of 50-200°C is 20-500 pts.mass.

Description

  The present invention relates to a primer composition and a laminate obtained by using the primer composition.

  Polytetrafluoroethylene (hereinafter also referred to as “PTFE”), tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer (hereinafter also referred to as “PFA”), tetrafluoroethylene / hexafluoropropylene copolymer (hereinafter referred to as “PFA”) Hereinafter, also referred to as “FEP”), polychlorotrifluoroethylene (hereinafter also referred to as “PCTFE”), ethylene / tetrafluoroethylene copolymer (hereinafter also referred to as “ETFE”), polyvinylidene fluoride (hereinafter referred to as “ETFE”). Hereinafter, fluorine-containing polymers such as “PVDF” and ethylene / chlorotrifluoroethylene copolymer (hereinafter also referred to as “ECTFE”) are heat-resistant, chemical-resistant, non-adhesive, and lubricated. Excellent in heat resistance, weather resistance, gas barrier properties, etc., used in various fields such as semiconductor industry, automobile industry and chemical industry It has been. In particular, powder made of a fluoropolymer having a particle size of 100 μm or less is coated to improve non-stickiness, lubricity and chemical resistance on the surface of heat-resistant substrates, and is used for kitchen appliances, containers and tanks. Used for surface processing of pipes, joints, etc.

  In general, the fluoropolymer is applied after surface roughening treatment such as sandblasting on the surface of the base material. However, since the adhesion to the base material is low, a primer composition for coating the fluoropolymer is obtained. Proposed. Under such circumstances, a powder primer composition using a reactive fluoropolymer having a reactive group in the molecule of the fluoropolymer is known (for example, Patent Document 1). Moreover, the primer composition using a silane coupling agent is known (for example, patent document 2). Furthermore, a primer composition containing water, an organic solvent, an adhesive resin precursor, and a fluoropolymer is known (for example, Patent Document 3). In addition, it is known that a fluorine-containing polymer particle is dispersed and applied using a fluorine-containing dispersion medium (for example, Patent Document 4).

JP 2006206637 A Japanese Patent Laid-Open No. 2006-167689 Japanese Examined Patent Publication No. 4-28032 Japanese Patent Publication No.57-15607

  However, there is a demand for better adhesion between the fluoropolymer coating film and the substrate than the primer compositions described in Patent Document 1 and Patent Document 2. In general, the specific gravity of the fluoropolymer is about 1.5 to 2.2, which is considerably larger than the specific gravity of water. Therefore, in the primer composition of Patent Document 3, the fluoropolymer tends to settle, It is not easy to use. Patent Document 4 does not describe a primer composition. Trichlorotrifluoroethane (hereinafter also referred to as “CFC-113”), which is a low-boiling fluorine-containing dispersion medium exemplified in Patent Document 4, has a low boiling point and is easy to dry. Only illustrated. In addition, according to the study by the present inventors, a primer composition containing a powder composed of CFC-113 and an adhesive resin swells in CFC-113, so that the dispersion state becomes unstable and used. I found it not easy to do. Furthermore, the primer composition which uses the water containing the surfactant illustrated by patent document 4 as a dispersion medium also discovered that the powder which consists of a fluoropolymer tends to settle, and is not easy to use.

  An object of the present invention is to solve the conventional problems as described above, and to provide a primer composition excellent in adhesion to a substrate and excellent in dispersion stability and a laminate obtained using the same. .

The present invention comprises the following.
The present invention contains a powder (X) made of a reactive fluorine-containing polymer, a powder (Y) made of an adhesive resin, and a fluorine-containing dispersion medium (Z) having a boiling point of 50 to 200 ° C., The content of the powder (Y) made of an adhesive resin is 1 to 30 parts by weight and the boiling point is 50 to 200 ° C. with respect to 100 parts by weight of the powder (X) made of a reactive fluoropolymer. It is related with the primer composition whose content of a fluorine dispersion medium (Z) is 20-500 mass.
The present invention relates to a laminate in which a primer layer, which is a heat-treated product of the primer composition, and a topcoat layer made of a fluororesin are laminated in this order on a substrate surface.

  According to the present invention, it is possible to provide a primer composition excellent in adhesiveness to a substrate and excellent in dispersion stability and a laminate obtained using the same.

  In this specification, the term “process” is not limited to an independent process, and is included in the term if the intended purpose of the process is achieved even when it cannot be clearly distinguished from other processes. . Moreover, the numerical range shown using "to" shows the range which includes the numerical value described before and behind "to" as a minimum value and a maximum value, respectively. Furthermore, the content of each component in the composition means the total amount of the plurality of substances present in the composition unless there is a specific notice when there are a plurality of substances corresponding to each component in the composition.

(Primer composition)
The primer layer formed from the primer composition of the present invention is excellent in adhesiveness with a base material, particularly in adhesiveness with a base material and adhesiveness with a topcoat layer made of a fluororesin provided on the primer layer. Excellent. The primer composition is excellent in storage stability. Furthermore, it is excellent in applicability and a coating layer with high uniformity can be easily obtained.

  After applying the primer composition to the substrate surface, the primer layer obtained by heat treatment is firmly fixed to the substrate surface, and has sufficient adhesive force with the fluorine-containing resin applied thereon. Therefore, the surface of the primer layer, which is a heat-treated product of the primer composition, is highly adhered to the surface of the substrate by recoating a powder made of fluorine-containing resin or a topcoat composition containing powder containing a fluorine-containing resin. It is possible to obtain a topcoat layer which is a coating film of a fluororesin having a necessary film thickness while having properties.

[Powder made of reactive fluoropolymer (X)]
The powder (X) made of a reactive fluorine-containing polymer is a repeating unit based on a fluorine-containing monomer, a functional group capable of causing a crosslinking reaction (hereinafter also referred to as “crosslinkable functional group”) and a polymerizable unsaturated bond. And a reactive unit containing a repeating unit based on another monomer that can be copolymerized with a fluorine-containing monomer as necessary. A powder made of a fluoropolymer. The powder (X) made of the reactive fluoropolymer may be a single type or a combination of two or more types.

<Repeating unit based on fluorine-containing monomer>
Although it does not specifically limit as a fluorine-containing monomer, Fluoroolefin which does not have a hydrogen atom in unsaturated groups, such as tetrafluoroethylene (henceforth "TFE"), hexafluoropropylene, chlorotrifluoroethylene, perfluoro (propyl) And fluoroethylene having a hydrogen atom in an unsaturated group such as perfluoro (alkyl vinyl ether) such as vinyl ether), vinylidene fluoride, vinyl fluoride, and trifluoroethylene. As the fluorine-containing monomer, TFE, perfluoro (alkyl vinyl ether) such as perfluoro (propyl vinyl ether), hexafluoropropylene, chlorotrifluoroethylene, and vinylidene fluoride are preferable.
A fluorine-containing monomer may be used individually by 1 type, and may use 2 or more types together.

The fluorine-containing monomer is also preferably used in combination with ethylene.
Therefore, monomers other than the crosslinkable monomer constituting the reactive fluoropolymer and combinations thereof, TFE, perfluoro (alkyl vinyl ether) such as perfluoro (propyl vinyl ether), hexafluoropropylene, chlorotrifluoroethylene, vinylidene fluoride, As a combination of a fluorine-containing monomer and optionally ethylene, a combination of TFE and ethylene, a combination of TFE and perfluoro (alkyl vinyl ether) such as perfluoro (propyl vinyl ether), or a combination of chlorotrifluoroethylene and ethylene is preferable. Examples of the polymer obtained by a combination of the preferred fluorine-containing monomers include PTFE, PFA, FEP, ETFE, PCTFE, PVDF, ECTFE, etc., ETFE, PFA and ECTFE are preferred, and ETFE is particularly preferred. If it is a monomer other than the crosslinkable monomer constituting the preferred polymer and a combination thereof, the primer layer tends to have a melting point that is easy to heat-treat the primer composition while having heat resistance and chemical resistance. is there.

<Repeating unit based on a monomer having a functional group capable of causing a crosslinking reaction and a polymerizable unsaturated bond>
The powder (X) comprising a reactive fluoropolymer is a repeating unit based on a monomer having a functional group capable of causing at least one crosslinking reaction and a polymerizable unsaturated bond (hereinafter referred to as “repeating unit (C1)”. Also called). The repeating unit (C1) is formed by polymerizing a monomer having a functional group capable of causing a crosslinking reaction and a polymerizable unsaturated bond with itself or a fluorine-containing monomer.

<< Functional group capable of causing cross-linking reaction >>
Examples of the functional group capable of causing a crosslinking reaction include a carboxy group, an alkoxycarbonyl group (hereinafter also referred to as “ester group”), a carbonyl fluoride group (hereinafter also referred to as “fluoroformyl group”), an alkoxycarbonyloxy group ( Hereinafter, also referred to as “carbonate group”), acid anhydride group, amide group, epoxy group, hydroxyl group, amino group, carboxy group, alkoxycarbonyl group, carbonyl fluoride group, and acid anhydride group are preferable, An acid anhydride group is particularly preferred. When the crosslinkable group is a carboxy group, an alkoxycarbonyl group, a carbonyl fluoride group or an acid anhydride group, the adhesive property tends to be more excellent, and when the crosslinkable functional group is an acid anhydride group, There is a tendency that a powder (X) comprising a reactive fluoropolymer is easily obtained. The acid anhydride group may have an acid anhydride group derived from the monomer as it is, or may have an acidic functional group obtained by hydrolysis of the acid anhydride group.

Monomers having a crosslinkable functional group and a polymerizable unsaturated bond, in which the crosslinkable functional group is an acid anhydride group, are maleic anhydride, itaconic anhydride (hereinafter also referred to as “IAH”), citraconic anhydride ( Hereinafter, also referred to as “CAH”), 5-norbornene-2,3-dicarboxylic acid anhydride and the like. IAH and CAH are preferred, and IAH is particularly preferred. When IAH or CAH is used, there is a tendency that a primer composition having better adhesion is obtained.
A crosslinkable functional group may be used individually by 1 type, and may use 2 or more types together.

<Repeating units based on other monomers>
The reactive fluorine-containing polymer is a repeating unit (D) based on another monomer other than the unit based on the above-mentioned fluorine-containing monomer and the unit based on the monomer having a crosslinkable functional group and a polymerizable unsaturated bond (hereinafter, (Also referred to as “repeating unit (D)”).

Other monomers other than ethylene constituting the repeating unit (D) include hydrocarbon olefins having 3 or more carbon atoms such as propylene and butene, alkyl vinyl ethers, glycidyl vinyl ethers, hydroxybutyl vinyl ethers, methylvinyloxybutyl carbonates and the like. Vinyl ether (excluding perfluoro (alkyl vinyl ether)), vinyl acetate, vinyl chloroacetate, vinyl butanoate, vinyl pivalate, vinyl benzoate, vinyl crotonate, etc., CH ₂ ═CX (CF ₂ ) _n Y (Wherein, X and Y are each independently hydrogen or a fluorine atom, and n is an integer of 1 to 8.), (polyfluoroalkyl) acrylate, (polyfluoroalkyl) Polyfluoroal such as methacrylate Le (meth) acrylic acid ester.

CH ₂ = CX _{(CF 2)} a compound represented by _n Y are those more preferably n = 2 to 4. Specific examples of the compound represented by CH ₂ ═CX (CF ₂ ) _n Y in which n = 2 to 4 include CH ₂ ═CF (CF ₂ ) ₂ F, CH ₂ ═CF (CF ₂ ) ₃ F, _{CH 2 = CF (CF 2)} 4 F, CH 2 = CF (CF 2) 2 H, CH 2 = CF (CF 2) 3 H, CH 2 = CF (CF 2) 4 H, CH 2 = CH (CF _{2) 2 F, CH 2 =} CH (CF 2) 3 F, CH 2 = CH (CF 2) 4 F, CH 2 = CH (CF 2) 2 H, CH 2 = CH (CF 2) 3 H, CH ₂ = CH (CF ₂ ) ₄ H and the like. Further, CH ₂ = CF (CF ₂ ) ₂ F, CH ₂ = CH (CF ₂ ) ₂ F, CH ₂ = CH (CF ₂ ) ₂ H or CH ₂ = CF (CF ₂ ) ₂ H is more preferable, and CH ₂ = CH (CF ₂ ) ₂ F is particularly preferred.
Another monomer may be used individually by 1 type and may use 2 or more types together.

<Preferable content of each unit>
The ratio of the crosslinkable functional group in the reactive fluorine-containing polymer is such that the number of moles of the repeating unit based on the monomer having the crosslinkable functional group and the polymerizable unsaturated bond is (C1), and the repeating unit based on the fluorine-containing monomer. (C1) / (P) is 1 / 10,000 or more, preferably 1 / 10,000 to 5/100, and preferably 3 / 2,000 to 3/100. More preferred is 3 / 1,000 to 3/100. When (C1) / (P) is 1 / 10,000 or more, the chemical reaction with the powder (Y) made of an adhesive resin is increased in the firing step for producing the primer layer, and the base material Higher adhesion to can be obtained. Moreover, when (C1) / (P) is 5/100 or less, chemical resistance and heat resistance tend to be improved.
In addition, the repeating unit based on a fluorine-containing monomer contains the repeating unit based on ethylene depending on the case.

  When the monomer having a crosslinkable functional group and a polymerizable unsaturated bond is a monomer having an acid anhydride group and a polymerizable unsaturated bond, it is based on the monomer having an acid anhydride group and a polymerizable unsaturated bond. When the number of moles of the repeating unit is (C2) and the number of moles of the unit based on the fluorine-containing monomer is (P), (C2) / (P) is 1 / 10,000 or more, and 1 / 10,000. To 5/100 is preferable, 3 / 2,000 to 3/100 is more preferable, and 3 / 1,000 to 3/100 is particularly preferable. When (C2) / (P) is 1 / 10,000 or more, the chemical reaction with the powder (Y) made of an adhesive resin is increased in the firing step for producing the primer layer, and the base material Higher adhesion to can be obtained. Further, when (C2) / (P) is 5/100 or less, chemical resistance and heat resistance tend to be improved.

  Therefore, as the powder (X) made of a reactive fluoropolymer, a repeating unit (A) based on TFE (hereinafter also referred to as “repeating unit (A)”), a repeating unit (B) based on ethylene (hereinafter referred to as “repeating unit (A)”). And a repeating unit (C2) based on a monomer having an acid anhydride group and a polymerizable unsaturated bond, and (A) / (B) in a molar ratio of 20 From a reactive ethylene / tetrafluoroethylene copolymer in which (C2) / ((A) + (B)) is 1 / 10,000 to 5/100 in molar ratio. It is particularly preferable to be a powder (hereinafter also referred to as “reactive ETFE powder”). In the reactive ETFE powder, the ratio of the repeating unit (A) to the repeating unit (B) is 20/80 to 80/20, preferably 50/50 to 70/30, in terms of molar ratio. When (A) / (B) is 20/80 or more, heat resistance, weather resistance, chemical resistance, and gas barrier properties tend to be further improved, and (A) / (B) is 80/20 or less. And there exists a tendency for mechanical strength and a meltability to improve more.

  The content of the repeating unit (D) is preferably from 0 to 20 mol%, more preferably from 0 to 15 mol%, particularly preferably from 0 to 10 mol%, based on all repeating units in the reactive fluoropolymer.

  In the present invention, the contents of the repeating units (C1), (C2), (P), (A), (B), and (D) are substantially the same as the charged amount of the monomer constituting each repeating unit.

<Melting point>
Although melting | fusing point of a reactive fluoropolymer is not specifically limited, 150-350 degreeC is preferable, 200-330 degreeC is more preferable, 220-310 degreeC is especially preferable. When the melting point of the reactive fluoropolymer is in the range of 150 to 350 ° C., heat treatment is easy, and the obtained coating film tends to have excellent mechanical properties, heat resistance, and chemical resistance.

<Melt flow rate value>
The reactive fluoropolymer is a melt flow rate value at 300 ° C. within the range of the heat treatment temperature of the primer composition layer described later of the reactive fluoropolymer (hereinafter referred to as “MFR value”). However, it is preferably 1 to 1000 g / 10 minutes, more preferably 5 to 200 g / 10 minutes, and particularly preferably 10 to 100 g / 10 minutes.
If the MFR value is 1 g / 10 min or more, the coating film tends to be smoothed during heat treatment, and if it is 1000 g / 10 min or less, the mechanical strength of the coating film tends to be improved. There is a tendency that the occurrence of uneven thickness is suppressed. The MFR value is obtained by a measurement method based on ASTM-D3159.
The MFR of a reactive ethylene / tetrafluoroethylene copolymer (hereinafter also referred to as “reactive ETFE”), which is a reactive fluoropolymer in the reactive ETFE powder, is a flow made by Shimadzu Corporation. The extrusion rate of reactive ETFE when extruding into an orifice having a diameter of 2.1 mm and a length of 8 mm under a temperature of 300 ° C. and a load of 7 kg using a tester.

  By measuring the MFR value, it can be used as a measure of the molecular weight. When MFR which is high temperature fluidity is large, it means that the molecular weight is low, and when MFR is small, it indicates that the molecular weight is high. In addition, although it is thought that the mass average molecular weight of a reactive fluoropolymer can generally be 10,000-10,000,000, since a fluoropolymer does not melt | dissolve in a solvent, the direct measurement of molecular weight is Have difficulty. Here, the weight average molecular weight is a molecular weight in terms of PMMA (polymethyl methacrylate) by gel permeation chromatography (GPC).

<Average particle size>
Although the average particle diameter of powder (X) which consists of a reactive fluoropolymer is not specifically limited, It can be 0.1-100 micrometers, 1-70 micrometers is preferable and 5-50 micrometers is more preferable. If the average particle diameter of the powder (X) made of the reactive fluoropolymer is 1 μm or more, a stable powder tends to be obtained more easily. The powder made of the reactive fluoropolymer ( When the average particle size of X) is 100 μm or less, the particles do not settle in a short time in the primer composition, so that the storage stability tends to be improved. The average particle diameter of the powder (X) made of a reactive fluoropolymer is a volume-based median diameter measured using a laser diffraction / scattering particle size distribution apparatus.

<Preparation method>
Although the manufacturing method of powder (X) which consists of a reactive fluoropolymer is not specifically limited, The method of grind | pulverizing after manufacturing a reactive fluoropolymer is mentioned. Although the manufacturing method of a reactive fluoropolymer is not specifically limited, It manufactures by a well-known method. For example, although the manufacturing method of reactive ETFE is not specifically limited, The method disclosed by Unexamined-Japanese-Patent No. 2004-238405 is mentioned.

  The pulverization may be performed by spray-drying a dispersion containing a reactive fluoropolymer after polymerization, or by agglomerating and drying the fluoropolymer to obtain particles obtained by hammer mill, turbo mill, cutting mill, crusher, jet A method of pulverizing with a pulverizer such as a mill or a counter jet mill, and a method of mechanically pulverizing at a low temperature below room temperature at which the reactive fluoropolymer becomes brittle (hereinafter also referred to as “freezing pulverization”). Freeze pulverization is preferred.

  Freeze pulverization tends to be pulverized without being affected by the softening temperature of the fluoropolymer. In the case of freeze pulverization, pulverization is performed while cooling with a cooling medium such as liquefied carbon dioxide or liquid nitrogen. As a freeze pulverization apparatus, a freeze pulverizer manufactured by AS ONE, a Linrex mill manufactured by Hosokawa Micron, etc. can be used, and the temperature during pulverization is preferably -200 to 20 ° C, more preferably -180 to -20 ° C. -150--50 degreeC is especially preferable.

  The particle size of the powder (X) made of the reactive fluoropolymer may be adjusted by classification using a sieve or an air stream.

[Powder made of adhesive resin (Y)]
The powder (Y) made of an adhesive resin is a powder of an adhesive resin that is solid at room temperature (for example, 25 ° C.). An adhesive resin has a melting point, a glass transition temperature, or a thermal decomposition start temperature not lower than room temperature and not higher than the heat treatment temperature of the reactive fluoropolymer, and is bonded by a crosslinking reaction of the adhesive resin in the heat treatment step of the primer composition. A resin that exhibits its properties. The adhesive resin is preferably one that can cause a chemical crosslinking reaction with the powder (X) made of a reactive fluoropolymer in addition to the crosslinking reaction of the adhesive resin alone. By this crosslinking reaction, the heat-treated product of the primer composition exhibits a strong adhesive effect as a coating film on the substrate. Here, melting | fusing point, glass transition temperature, and thermal decomposition start temperature can each be measured using a conventional means.

  Specific examples of the powder (Y) made of adhesive resin include powder made of epoxy resin, powder made of phenoxy resin, melamine cyanurate powder, powder made of polyethersulfone resin, powder made of polyamide resin. Powder made of polyamideimide resin, powder made of polyphenylene sulfide resin, powder made of polyetherimide resin, powder made of polyetheretherketone resin, powder made of polysulfone resin, powder made of polyurethane resin, Examples include powder made of polyvinyl alcohol resin, powder made of polyethylene oxide resin, powder made of silicone resin, powder made of epoxy resin, powder made of phenoxy resin, powder made of melamine cyanurate, poly Powder made of ether sulfone resin, from polyamide resin Rukonatai, powder of a polyamide-imide resin, a powder composed of polyphenylene sulfide resin, powder consisting of a polyetherimide resin and the like are preferable. When the primer composition contains a powder composed of the preferred adhesive resin, a high adhesive force tends to be obtained.

  Epoxy resin is bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol AD type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, glycidyl ester type epoxy resin obtained by condensation reaction of bisphenol A and epichlorohydrin. , Biphenyl type epoxy resins, polymer type epoxy resins, and other modified epoxy resins.

Among these, a bisphenol A type epoxy resin having a basic chemical structure shown below is excellent in adhesive strength and heat resistance, and those having a softening point of room temperature or higher are preferable because the dispersion state is stabilized in the primer composition.

(In formula, m is an integer greater than or equal to 1, and the integer of 1-30 is preferable.)

  Specifically, the bisphenol A type epoxy resin is a jER (registered trademark) series manufactured by Mitsubishi Chemical Corporation (No. 1001, No. 1003, No. 1004, No. 1009, No. 1010), DIC Corporation. Among the manufactured EPICLON (registered trademark) series, those having a softening point of room temperature or higher (No. 1050, No. 2050, No. 3050, No. 4050, No. 7050, HM-091, HM-101) and the like can be mentioned. .

In the present invention, the basic chemical structure of the phenoxy resin is the same as that of the bisphenol A type epoxy resin, but those having a particularly high molecular weight (for example, having a molecular weight of 10,000 or more) are distinguished as phenoxy resins.
Specific examples of the phenoxy resin include jER (registered trademark) series (No. 1256, No. 4250, No. 4275) manufactured by Mitsubishi Chemical Corporation, and phenoxy resin (No. PKHB, PKHC, PKHH, PKHJ, PKFE manufactured by InChem). ), And the like.

The polyamide resin is a crystalline linear polymer in which a repeating unit of an amide bond constitutes a main chain. In addition to nylon 4, nylon 6, nylon 11, nylon 12, nylon 46, nylon 66, nylon 610, etc., In addition to aliphatic polyamide resins, aromatic polyamide resins such as aramid can also be used.
Specific examples of the polyamide resin include Best Zint (registered trademark) series (No. 2070, No. 2159, No. 2158, MSP-100, MSP-S, MSP-B10) manufactured by Daicel Evonik. It is done.

Melamine cyanurate powder

An organic salt powder composed of melamine and isocyanuric acid having a basic chemical structure represented by the following, specifically, Nissan's TEPIC (registered trademark) series (TEPIC-S, TEPIC-SS), Sakai Chemical Co., Ltd. Examples include STABACE (registered trademark) series (MC-5S).

Polyethersulfone resin

(In the formula, p is an integer of 1 or more.)
It is a polymer compound having the basic chemical structure represented by Specific examples of the polyethersulfone resin include Sumika Excel (registered trademark) series (3600P, 4100P, 4800P, 5003P) manufactured by Sumitomo Chemical Co., Ltd.

Polyamideimide resin

(In the formula, q is an integer of 1 or more. Ar is an arylene group having 6 to 20 carbon atoms (phenylene, naphthylene, etc.).)
It is a polymer compound having the basic chemical structure represented by Specific examples of the polyamideimide resin include TORLON (registered trademark) series (4000T, 4000TF) manufactured by Solvay Solexis.

Polyphenylene sulfide resin

(In the formula, r is an integer of 1 or more.)
It is a polymer compound having the basic chemical structure represented by Specific examples of the polyphenylene sulfide resin include Trepearl (registered trademark) PPS manufactured by Toray Industries, Inc.

Polyetherimide resin

(In the formula, s is an integer of 1 or more.)
It is a polymer compound having the basic chemical structure represented by Specific examples of the polyetherimide resin include Ultem (registered trademark) 1000P and 1010P manufactured by SABIC Innovative Plastics.

<Average particle size>
The average particle diameter of the powder (Y) made of an adhesive resin is not particularly limited, but may be 1 to 1,000 μm, preferably 1 to 100 μm, and more preferably 2 to 70 μm. 5 to 50 μm is particularly preferable. If the average particle size of the powder (Y) made of an adhesive resin is 1 μm or more, the reaction is less likely to occur during storage, and the storage stability tends to be improved. Tend to improve. The average particle diameter of the powder (Y) made of an adhesive resin is a volume-based median diameter when measured using a laser diffraction / scattering particle size distribution apparatus.

<Preparation method>
The method for producing the powder (Y) made of an adhesive resin is not particularly limited, but commercially available adhesive resin particles that are solid at room temperature (for example, 25 ° C.) are pulverized so as to have the preferred average particle diameter. The method of doing is mentioned. As a pulverization method, a method of pulverizing with a pulverizer such as a hammer mill, a turbo mill, a cutting mill, a ball mill, a bead mill, a crusher, a jet mill, a counter jet mill or the like, or a freeze pulverization method at a low temperature may be used. Moreover, when the powder consisting of commercially available adhesive resin has the said suitable average particle diameter, it can use as it is.
The particle size of the powder (Y) made of an adhesive resin may be adjusted by classification using a sieve or an air current.

  The content of the powder (Y) made of an adhesive resin is 1 to 30 parts by weight, preferably 2 to 25 parts by weight, based on 100 parts by weight of the powder (X) made of a reactive fluoropolymer. 3 to 20 parts by mass is particularly preferable. If the content of the powder (Y) made of an adhesive resin with respect to 100 parts by weight of the powder (X) made of a reactive fluoropolymer is less than 1 part by weight, the adhesive force is lowered and is more than 30 parts by weight. And the thermal decomposition of the adhesive resin tends to cause foaming and discoloration of the primer layer.

[Fluorine-containing dispersion medium (Z) having a boiling point of 50 to 200 ° C.]
In the present invention, the primer composition contains a fluorine-containing dispersion medium (Z) having a boiling point of 50 to 200 ° C. (hereinafter also referred to as “fluorine-containing dispersion medium (Z)”). Since the fluorine-containing dispersion medium (Z) used in the present invention has a low surface tension, it has good permeability to the powder (X) made of a reactive fluorine-containing polymer, and has a low foaming rate during stirring. Easy to mix.

  The fluorine-containing dispersion medium (Z) has a carbon atom and a fluorine atom in the molecule, and optionally has an oxygen atom and a chlorine atom. Although it does not specifically limit as a fluorine-containing dispersion medium (Z), The fluorine-containing dispersion medium containing a hydrofluorocarbon, hydrofluoroether, and a chlorine atom is mentioned. In the present invention, the hydrofluorocarbon and hydrofluoroether do not contain a chlorine atom in the molecule.

The hydrofluorocarbon is not particularly limited, but CHF ₂ CF ₂ CF ₂ CF ₂ CF ₂ CF ₃ , CF ₃ CF ₂ CF ₂ CF ₂ CH ₂ CH ₃ , CF ₃ CF ₂ CF ₂ CF ₂ CF ₂ CF ₂ CH ₂ CH _{3, CF 3 CF 2 CHFCHFCF 3} , CF 3 CH is _{2 CF 2 CH 3, CF 3} CF 2 CF 2 CFHCH 3 like. Of _{these, CHF 2 CF 2 CF 2 CF} 2 CF 2 CF 3 and _{CF 3 CF 2 CF 2 CF 2} CF 2 CF 2 CH 2 CH 3 is has a suitable drying rate, particularly preferred.

The hydrofluoroether is not particularly limited, but CF ₃ CH ₂ OCF ₂ CF ₂ H, CF ₃ CH ₂ OCF ₂ CFHCF ₃ , (CF ₃ ) ₂ CHOCF ₂ CF ₂ H, CF ₃ CH ₂ OCHFCHF ₂ , CF ₃ ( CF ₂ ) ₃ OCH ₃ , CF ₃ (CF ₂ ) ₄ OCH ₃ , CF ₃ (CF ₂ ) ₃ OCH ₂ CH ₃ , CF ₃ (CF ₂ ) ₄ OCH ₂ CH ₃ , (CF ₃ ) ₂ CF ₂ CF ₂ include OCH ₂ CH _{3 but, CF 3 CH 2 OCF 2 CF} 2 H are preferred.

Fluorinated dispersion medium containing chlorine atoms is not particularly _{limited, CF 3 CF 2 CHCl 2,} CClF 2 CF 2 CHClF, CF 3 CHCl 2, CFCl 2 CH 3 and the _like, CF ₃ CF ₂ CHCl 2 and CClF ₂ CF ₂ CHClF is preferred.

  The fluorine-containing dispersion medium (Z) preferably contains no chlorine atom in the molecule, and more preferably a hydrofluorocarbon and a hydrofluoroether. A fluorine-containing dispersion medium that does not contain a chlorine atom in the molecule has an ozone depletion coefficient of zero and a relatively small global warming coefficient, which tends to be favorable in terms of the environment. Moreover, since hydrofluorocarbon and hydrofluoroether have a large specific gravity of about 1.4 or more, the powder (X) made of a reactive fluoropolymer is difficult to settle, and a primer composition having excellent storage stability is obtained. Tend to be able to. Hydrofluorocarbons and hydrofluoroethers are nonflammable and have excellent safety. In general, the specific gravity of a fluoropolymer is as large as 1.5 to 2.2. Therefore, when powder (X) made of a reactive fluoropolymer is dispersed in water and an organic solvent having no fluorine atom Moreover, it settles in a short time and becomes difficult to handle as a primer composition.

  The boiling point of the fluorine-containing dispersion medium (Z) is 50 to 200 ° C, preferably 55 to 180 ° C, particularly preferably 65 to 150 ° C. When the fluorine-containing dispersion medium has a boiling point of less than 50 ° C., drying is too fast, and thus, for example, when applied by a spray method, adhesion to the nozzle and nozzle clogging are likely to occur. Further, when the boiling point of the fluorine-containing dispersion medium is more than 200 ° C., the drying is too slow, so that the coated film is difficult to dry.

  The Kauri-butanol value (hereinafter also referred to as “KB value”) of the fluorine-containing dispersion medium (Z) is not particularly limited, but may be 30 or less, preferably 20 or less, and particularly preferably 10 or less. When the KB value of the fluorine-containing dispersion medium (Z) is more than 30, the fluorine-containing dispersion medium (Z) causes swelling and softening of the powder (Y) made of the adhesive resin, and in the adhesive resin dispersion liquid. Dispersion stability tends to decrease. The KB value indicates the number of ml when 20 g of a butanol solution of kauri resin is placed in an Erlenmeyer flask at 25 ° C., placed on a standard type paper, a dispersion medium is added, and the type cannot be read due to turbidity due to precipitation of the kauri resin. It is an indicator of solubility.

  From the above, the fluorine-containing dispersion medium (Z) is more preferably a hydrofluorocarbon or hydrofluoroether having a KB value of 30 or less.

  Content of a fluorine-containing dispersion medium (Z) is 20-500 mass parts with respect to 100 mass parts of powder (X) which consists of a reactive fluoropolymer, 50-400 mass parts is preferable, and 100- 300 parts by mass is particularly preferred. When the content of the fluorine-containing dispersion medium (Z) is less than 20 parts by mass with respect to 100 parts by mass of the powder (X) made of a reactive fluorine-containing polymer, the viscosity of the primer composition becomes higher. It is difficult to apply to the film, and the film thickness tends to be non-uniform. Further, when the content of the fluorine-containing dispersion medium (Z) is more than 500 parts by mass with respect to 100 parts by mass of the powder (X) made of a reactive fluorine-containing polymer, the viscosity of the primer composition is lower. Therefore, it is easy to sag between coating and drying, resulting in coating unevenness. In addition, content of a fluorine-containing dispersion medium (Z) can be selected so that a primer composition may become the optimal viscosity according to a coating method.

[Additional ingredients]
The primer composition can contain additional components within the range where the effects of the present invention are exhibited. Examples of such components include powders composed of non-reactive fluorine-containing polymers, colorants, reinforcing agents, organic solvents, heat stabilizers, and the like. The content of the further components is not particularly limited, but a total of 100 parts by mass of the powder (X) made of a reactive fluorine-containing polymer, the powder (Y) made of an adhesive resin, and the fluorine-containing dispersion medium (Z). The amount can be 100 parts by mass or less, preferably 0.1 to 20 parts by mass, and more preferably 0.1 to 10 parts by mass.

  The primer composition may contain a powder made of a non-reactive fluoropolymer. Here, the powder made of the non-reactive fluoropolymer is a molar ratio of (C1) / (P) in the definition of the powder (X) made of the reactive fluoropolymer. It means a powder composed of less than fluoropolymer. Except that (C1) / (P) is less than 1 / 10,000 in terms of molar ratio, the powder comprising a non-reactive fluoropolymer includes a powder comprising a reactive fluoropolymer, including preferred ones. As described above in (X). As specific examples of powders made of non-reactive fluoropolymers, Asahi Glass Co., Ltd. Fluoron (registered trademark) TL-081, Z-8820X, LM-2150 (all of which have crosslinkable functional groups and polymerizable unsaturated bonds) And a repeating unit based on a monomer having no (C1).

  The average particle size of the powder composed of the non-reactive fluoropolymer is preferably 1 to 1,000 μm, more preferably 5 to 300 μm, and particularly preferably 10 to 200 μm. When the average particle diameter of the powder made of the non-reactive fluoropolymer is 1 μm or more, the number of times of overcoating for processing to a predetermined thickness is reduced without being too small, and when it is 1,000 μm or less. There is a tendency that the smoothness of the surface is maintained. The average particle diameter of the powder made of a non-reactive fluoropolymer is a volume-based median diameter measured using a laser diffraction / scattering particle size distribution apparatus.

  The content of the powder composed of the non-reactive fluoropolymer is 50 with respect to 100 parts by mass in total of the powder (X) composed of the reactive fluoropolymer and the powder (Y) composed of the adhesive resin. It can be below mass part, it is preferable that it is 0.1-10 mass parts, and it is especially preferable that it is 0.1-3 mass parts.

  The primer composition includes pigments such as carbon black, graphite, cobalt blue, ultramarine, and titanium oxide as colorants, glass fibers as reinforcing materials, carbon fibers, carbon nanotubes, conductive carbon black, other synthetic resin powders, You may contain antiseptic | preservative etc. The content of these components can be 10 parts by mass or less with respect to a total of 100 parts by mass of the powder (X) made of a reactive fluoropolymer and the powder (Y) made of an adhesive resin. 0.1 to 5 parts by mass is preferable, and 0.1 to 3 parts by mass is particularly preferable.

Moreover, you may contain heat stabilizers, such as a copper compound, a tin compound, an iron compound, a lead compound, a titanium compound, and an aluminum compound, in the range which does not inhibit the adhesive effect of a primer composition. The specific surface area of the heat stabilizer is preferably 0.1 to 100 m ² / g, more preferably 1~70m ² / g, and particularly preferably 5 to 50 m ² / g. The specific surface area is based on the BET method. The content of the heat stabilizer can be less than 1 part by mass with respect to 100 parts by mass in total of the powder (X) made of a reactive fluoropolymer and the powder (Y) made of an adhesive resin. , Preferably less than 0.1 parts by mass, and more preferably not substantially contained.

  The primer composition may contain a small amount of an organic solvent such as ethanol, isopropyl alcohol, butanol, ethyl cellosolve, ethyl carbitol, toluene, xylene for the purpose of adjusting the drying rate as long as the stability of the liquid is not impaired. . Although content of an organic solvent is not specifically limited, It can be 0-20 mass parts with respect to 100 mass parts of fluorine-containing dispersion media (Z), and it is preferable that it is 0-10 mass parts.

[surface tension]
The surface tension of the primer composition is not particularly limited, but is preferably 30 mN / m or less, more preferably 25 mN / m or less, and particularly preferably 20 mN / m or less. If the surface tension is 30 mN / m or less, uneven thickness due to repelling or leveling tends to be suppressed. Although the minimum of the surface tension of a primer composition is not specifically limited, It is preferable that it is 15 mN / m or more. The surface tension can be controlled within a desired range by adjusting the type and amount of the fluorine-containing dispersion medium (Z).

[viscosity]
The viscosity of the primer composition is not particularly limited, but the measured value at 60 rpm with a rotational viscometer is preferably 10 to 10,000 mPa · s, more preferably 20 to 2,000 mPa · s, It is particularly preferably 50 to 800 mPa · s. When the viscosity of the composition is 10 mPa · s or more, dripping is suppressed from coating to drying, and when it is 10,000 mPa · s or less, the coating workability is good and the film thickness tends to be uniform. Tend. The viscosity is a value measured at 25 ° C. An example of the rotational viscometer is a Brookfield rotational viscometer. It is also possible to prepare a primer composition having a high viscosity and dilute it with a fluorine-containing dispersion medium (Z) so as to obtain an optimum viscosity according to the coating method.

  The thixotropy index value (hereinafter referred to as TI value) of the primer composition is not particularly limited, but is preferably in the range of 2 to 10. The TI value is a numerical value calculated by dividing a measured value of 6 rpm by a measured value of 60 rpm with a rotational viscometer, and can be made a suitable range by adjusting the concentration of the compounding agent or thickener. The TI value is more preferably in the range of 3-8, particularly preferably 3-7. When the TI value is 2 or more, it is difficult for the sagging to occur between coating and drying, the components in the composition are less likely to settle, the storage stability is improved, and when it is 10 or less, there is uneven coating. Even in such a case, smoothing by leveling tends to occur, bubbles tend to disappear, and film thickness unevenness tends not to occur. Furthermore, when the TI value is 2 to 10, suitable coating can be performed, and components in the composition are less likely to settle, and storage stability tends to be improved.

  In the present invention, the primer composition can be produced by mixing each component. The order of mixing the components is arbitrary, but the fluorine-containing dispersion medium (Z), the powder (X) made of a reactive fluorine-containing polymer, the powder (Y) made of an adhesive resin, and other components are added in this order. And can be mixed by stirring for about 1 to 60 minutes with a bladed stirrer.

(Laminate)
In the present invention, the laminate is obtained by laminating a primer layer, which is a heat-treated product of the primer composition, and a topcoat layer made of a fluororesin in this order on the substrate surface. In the laminate, an organic or inorganic coating layer that is a different material from the top coat layer may be further laminated on the surface of the top coat layer.
The laminate is excellent in durability such as heat resistance and alkali resistance, and adhesiveness.

[Base material]
The substrate in the present invention is not particularly limited, and examples thereof include metals such as iron, stainless steel, aluminum, copper, tin, titanium, chromium, nickel, and zinc, and heat-resistant materials such as glass and ceramics, and iron and stainless steel. Aluminum is preferred.

  The shape of the substrate in the present invention is not particularly limited, and examples thereof include pipes, tubes, films, plates, tanks, rolls, vessels, valves, elbows, etc., and various containers, pipes, tubes, tanks, pipes, joints. , Rolls, autoclaves, heat exchangers, distillation towers, jigs, valves, stirring blades, tank trucks, pumps, blower casings, centrifuges, cooking equipment, etc.

[Primer layer]
The primer layer is a heat-treated product of the primer composition. The primer composition is as described above including preferable ones. The thickness of the primer layer is preferably 1 to 1,000 μm, more preferably 5 to 500 μm, and particularly preferably 10 to 200 μm. When the thickness of the primer layer is 1 μm or more, the adhesiveness is sufficiently exhibited, and when it is 1,000 μm or less, foaming and blistering tend not to occur.

[Topcoat layer]
The topcoat layer made of a fluororesin is a layer obtained by applying and curing a powder topcoat composition containing a powder made of a fluororesin or a powder made of a fluororesin. Here, the top coat composition does not include powder (Y) made of the above-described adhesive resin.
Since the laminate has a topcoat layer, a coating film of a fluoropolymer having a required film thickness can be obtained while having high adhesion to the surface of the heat-resistant substrate.

<Powder topcoat composition containing powder made of fluororesin or powder made of fluororesin>
The powder made of fluororesin is a fluororesin powder that is solid at room temperature (for example, 25 ° C.). Although it does not specifically limit as a fluororesin, The homopolymer or copolymer of a fluorine-containing monomer is mentioned. Examples of the fluorine-containing monomer include the above-mentioned fluorine-containing monomer in the powder (X) composed of the above-described reactive fluorine-containing polymer. Further, the fluororesin may be a copolymer having the above-described monomers such as a crosslinkable monomer and other monomers as a comonomer component.

Examples of the fluororesin include the above-mentioned reactive fluoropolymers and non-reactive fluoropolymers. Nonreactive fluoropolymers are preferred, and nonreactive ethylene / tetrafluoroethylene copolymers (hereinafter referred to as “non-reactive fluoropolymers”). Also referred to as “reactive ETFE”). Since the non-reactive fluoropolymer is stable, the topcoat layer tends to be more stable. That is, in the present invention, the topcoat layer made of a fluororesin can be obtained by using a powder topcoat composition containing a powder made of a nonreactive fluororesin or a powder made of a nonreactive fluororesin. preferable.
The powder made of fluororesin may be used alone or in combination of two or more.

  The average particle diameter, MFR value, etc. of the fluororesin are as described above for the reactive fluoropolymer and the non-reactive fluoropolymer, including preferred ones.

The powder top coat composition containing a powder made of a fluororesin preferably contains the above-described heat stabilizer. The content of the thermal stabilizer, the powder topcoat composition 100 parts by weight, 1 × preferably ¹⁰ -8 to 5 parts by weight, 1 × and more preferably ¹⁰ -7 to 1 parts by weight, 5 × 10 ^{- 7} to 0.1 parts by weight is particularly preferred.

<Thickness of top coat layer>
As the thickness of the top coat layer, an optimum thickness can be selected in the range of 10 to 5,000 μm. A thickness of 10 to 100 μm is preferable for the purpose of improving water repellency, antifouling property and glossiness of the substrate surface, and a thickness of 50 to 500 μm is preferable for the purpose of improving lubricity and surface protection of the substrate surface. For the purpose of protecting the base material against chemicals and inorganic chemicals, a thickness of 200 to 1,000 μm is preferable, and a thickness of 1,000 to 5,000 μm is preferable particularly when very long-term durability is required. If it is too thin, the coating effect is not sufficient, and if it is too thick, the number of times of coating is increased, which is uneconomical and stress distortion due to the difference in thermal expansion coefficient from the substrate tends to occur, which is not preferable.

[Organic or inorganic coating layer that is a different material from the top coat layer]
Examples of the organic or inorganic coating layer (hereinafter also referred to as “further coating layer”), which is a material different from the top coat layer, include a colored layer, a hard coat layer, and a permeation prevention layer. When a laminated body contains the further coating layer, there exists a tendency for a laminated body to have further effects, such as a coloring effect, a hard-coat effect, and a penetration prevention effect. Although the thickness of the further coating layer is not specifically limited, It can be set to 0-1,000 micrometers, and it is preferable that it is 0-500 micrometers. The thickness of the further coating layer can be adjusted according to the properties imparted by the further coating layer.

[Peel strength]
In the laminate of the present invention, the adhesive force of the topcoat layer to the substrate can be examined by measuring the 90 ° peel strength. The higher the adhesive strength, the better. However, the peel strength is preferably 20 N / cm or more, more preferably 40 N / cm or more, and particularly preferably 50 N / cm or more. When the peel strength is less than 20 N / cm, the reliability of adhesion is low, and depending on the use environment, it may lead to peeling of the coating film or corrosion deterioration of the blister or substrate, which is not preferable.

(Laminate manufacturing method)
In the present invention, the laminate includes a step of obtaining a primer layer on the surface of the substrate and a step of obtaining a topcoat layer on the surface of the primer layer, and optionally a step of obtaining a further coating layer on the surface of the topcoat layer. It is obtained by the manufacturing method containing.

[Method for producing primer layer]
The primer layer is obtained by a production method including a step of forming the primer composition layer by applying the primer composition of the present invention to the substrate surface and a step of forming a primer layer by heat-treating the primer composition layer. . By the heat treatment, the fluorine-containing dispersion medium (Z) contained in the primer composition layer is removed, and the powder (X) made of a reactive fluorine-containing polymer and the powder (Y) made of an adhesive resin are respectively Independently, the powder (X) preferably made of a reactive fluoropolymer and the powder (Y) made of an adhesive resin are chemically reacted and cured to form a primer layer.

  A method for applying the primer composition is not particularly limited, and known liquid coating methods such as an air spray coating method, an airless spray coating method, a dip coating method, a brush coating method, and an electrostatic coating method can be applied. Among them, the air spray coating method or the airless spray coating method is preferable because it is simple and can coat a large area with a uniform thickness.

  The thickness of the primer composition layer formed on the surface of the base material includes preferable ones, and examples thereof include a thickness that becomes the thickness of the primer layer described above. Moreover, if the thickness of a primer composition exists in the said range, sufficient adhesiveness will be expressed by providing a primer composition once, but you may provide a primer composition in multiple times. In addition, the thickness of a primer composition can be adjusted according to the thickness of the primer layer after heat processing.

The application amount of the primer composition applied to the substrate surface is not particularly limited as long as it is an amount that can be the thickness of the primer composition layer described above, and is set to 1.6 to 1,600 g / m ² as a solid content. Is preferable, and it is more preferable to set it as 8.0-800 g / m < ² >.

  The heat treatment of the primer composition layer can be performed by any heating means such as an electric furnace, a gas furnace or an infrared heating furnace set to a predetermined temperature. The heat treatment temperature is preferably 260 to 340 ° C, more preferably 280 to 320 ° C, and particularly preferably 290 to 310 ° C. When the heat treatment temperature is 260 ° C. or higher, there is no tendency for adhesive strength reduction or remaining bubbles due to insufficient firing to occur, and when it is 340 ° C. or lower, discoloration and foaming tend to be suppressed. Although heat processing time changes with heat processing temperature, the heat processing for 1 to 180 minutes is preferable, More preferably, it is 5 to 120 minutes, Most preferably, it is 10 to 60 minutes. When the heat treatment time is 1 minute or longer, there is no tendency for adhesive strength reduction or bubble remaining due to insufficient firing to occur, and when it is 180 minutes or shorter, discoloration and foam formation tend to be suppressed.

  Prior to application of the primer composition, the substrate may be preheated at a temperature of 200 ° C. or lower. In addition, the surface of the substrate may be roughened by sandblasting, etching, metal spraying, or the like before applying the primer composition, and solvent cleaning may be performed to remove foreign matters attached to the surface. Thereby, there exists a tendency for adhesiveness to improve. Here, in the case of sandblasting, the surface roughness Ra can be processed in the range of 1 to 100 μm depending on the adhesiveness and application. In addition, after applying the primer composition of the present invention, prior to heat treatment, pretreatment is performed at a temperature of room temperature (for example, 25 ° C.) to about 200 ° C. to remove the fluorine-containing dispersion medium (Z) contained in the primer composition layer. You may keep it.

[Method for producing top coat layer]
The topcoat layer is obtained by applying a topcoat composition containing a powder made of a fluororesin or a powder made of a fluororesin to the surface of the primer layer laminated on the surface of the base material, A step of forming a topcoat composition layer containing a powder made of fluororesin, and a heat treatment of the powder layer made of fluororesin or the topcoat composition layer containing a powder made of fluororesin to form a topcoat layer It is obtained by a manufacturing method including a process.

  A method for applying a topcoat composition containing a powder made of a fluororesin or a powder made of a fluororesin is not particularly limited, but known powder coating methods such as an electrostatic coating method, a fluid dipping method, and a rotational molding method are available. Although it can be applied, the electrostatic coating method is preferable because it can be easily applied with a uniform thickness.

  The thickness of the topcoat composition layer containing a powder layer made of a fluororesin or a powder made of a fluororesin formed on the surface of the primer layer includes a preferable one, and a thickness that is the thickness of the topcoat layer described above Is mentioned. Further, if the thickness of the powder layer made of fluororesin or the topcoat composition layer containing the powder made of fluororesin is within the above range, the topcoat containing the powder made of fluororesin or the powder made of fluororesin It is sufficient to apply the composition once, but a topcoat composition containing a powder made of fluororesin or a powder made of fluororesin may be applied multiple times. In addition, the thickness of the topcoat composition layer containing the powder layer which consists of a fluororesin, or the powder which consists of a fluororesin can be adjusted according to the thickness after baking. When a top coat layer is formed a plurality of times, the top coat layers formed a plurality of times are collectively used as a top coat layer.

  The amount of the topcoat composition containing the powder made of fluororesin or the powder made of fluororesin to be applied to the surface of the primer layer is not particularly limited as long as it is an amount that makes the thickness of the topcoat layer described above.

  The heat treatment of the powder layer made of fluororesin or the topcoat composition layer containing the powder made of fluororesin is not particularly limited as long as the topcoat layer is formed on the surface of the primer layer, but is set to a predetermined temperature. The heating can be performed by any heating means such as an electric furnace, a gas furnace or an infrared heating furnace. The heat treatment temperature is preferably 260 to 340 ° C, more preferably 280 to 320 ° C, and particularly preferably 290 to 310 ° C. When the heat treatment temperature is 260 ° C. or higher, voids and bubble remaining due to insufficient firing are less likely to occur, and when it is 340 ° C. or lower, discoloration and foaming tend not to occur. Although heat processing time changes with heat processing temperature, the heat processing for 1 to 180 minutes is preferable, More preferably, it is 5 to 120 minutes, Most preferably, it is 10 to 60 minutes. If the heat treatment time is 1 minute or longer, bubbles remain due to insufficient firing, and if it is 180 minutes or less, discoloration and sagging tend not to occur.

[Method for producing an organic or inorganic coating layer that is a different material from the top coat]
The additional coating layer includes a step of applying a composition for an organic or inorganic coating layer, which is a material different from the top coat, to the surface of the top coat layer, and a method of forming the additional coating layer. Is obtained. The thickness of the organic or inorganic coating layer, which is a material different from the top coat, is not particularly limited, and examples thereof include a thickness that is the thickness of the further coating layer. The conditions for the composition for the further coating layer and the method for producing the further coating layer are not particularly limited, and examples include the conditions that are usually used for forming the further coating layer.

  The present invention will be described in detail below with reference to examples, but the present invention is not limited thereto. Examples 1 to 7 are examples, and examples 8 to 11 are comparative examples. In addition, application | coating and evaluation of each example followed the method as described below.

[Coating thickness] Five points were measured with an electromagnetic film thickness meter, and an average value was obtained.
[Viscosity] Viscosity was measured at 25 ° C using a Brookfield rotational viscometer.
[Surface Tension] The surface tension was measured at 25 ° C. using a Dunui type surface tension meter.
[MFR] Using a flow tester manufactured by Shimadzu Corporation, measure the MFR by measuring the extrusion rate of reactive ETFE when extruding into an orifice with a diameter of 2.1 mm and a length of 8 mm under a temperature of 300 ° C. and a load of 7 kg. did.

[Judgment of appearance] If there is no abnormality in the coating film appearance of the substrate with the primer layer or the coating test piece, it is ranked A. If the film is uneven or uneven, such as uneven coating thickness, bubbles or blisters, etc. When abnormalities were confirmed, they were ranked according to the following criteria, and D rank was not possible.
Very uniform appearance: A rank
Uniform appearance: B rank
Some abnormalities are seen: Rank C
Significant abnormalities are observed: D rank [dispersion workability] When applying the primer composition, whether there is an abnormality such as powder adhering to the nozzle or nozzle clogging is ranked according to the following criteria. did.
No abnormality: Rank A
Slightly powder adheres to the nozzle: B rank
Large amount of powder adheres to nozzle: C rank
Nozzle clogging and spraying cannot be continued: D rank

[Initial Adhesion Evaluation] The surface of the coating test piece was cut at 10 mm intervals using a cutter knife, and after peeling a part of the coating film, it was fixed to the chuck of a tensile tester and 90 degrees at a pulling speed of 50 mm / min. The peel strength was measured. The ranking was based on the following criteria, and D rank was not possible.
Peel strength ≧ 50.0 N / cm: A rank
40.0 or more and less than 50.0 N / cm: B rank
20.0 or more and less than 40.0 N / cm: C rank
<20.0 N / cm 2: D rank [heat resistant water] coating test piece was treated with a pressure cooker (high temperature steam pressure cooker) at 130 ° C. for 24 hours, and then the peel strength of the topcoat layer was measured in the same manner as in the initial adhesion evaluation. . The obtained peel strength after the hot water resistance test was ranked in the same manner as the evaluation of the initial peel strength.
[Alkali Resistance] The coated test piece was immersed in a 10% aqueous sodium hydroxide solution at 80 ° C. for 300 hours, and then the peel strength of the topcoat layer was measured in the same manner as in the initial adhesion evaluation. The obtained peel strength after the alkali resistance test was ranked in the same manner as the evaluation of the initial peel strength.
[Average Particle Size] Each powder was dispersed in a 0.1% aqueous surfactant solution, and the average particle size was measured using a laser scattering particle size distribution analyzer LA-920 manufactured by Horiba.
[Storage stability] Put the primer composition in a glass sample bottle with an internal volume of 100 cc and store it at 25 ° C for 300 hours. Ranking was performed based on the number of times the distribution was possible.
Less than 50 times re-distribution: Rank A
51-100 times: B rank
101-200 times: C rank
201 times or more: D rank

[Example 1]
<Production of Reactive Fluoropolymer-Containing Powder (Reactive FR-1)>
As a reactive fluoropolymer, a repeating unit based on TFE / a repeating unit based on ethylene / a repeating unit based on IAH / a repeating unit based on CH ₂ ═CH (CF ₂ ) ₄ F is in a molar ratio of 57.6 / 40. 0 / 1.8 / 0.6 (that is, (C2) / ((A) + (B)) is 1.84 / 100 in molar ratio) and ETFE having a melting point of 242 ° C. is a solution Particles obtained by polymerization and granulation were pulverized by a freezing pulverizer TPH-01 manufactured by AS ONE to obtain reactive ETFE powder (reactive FR-1) having an average particle diameter of 20 μm. The MFR value was 25 g / 10 minutes.

<Manufacture of powder (EP) made of adhesive resin>
Powder (EP) made of Mitsubishi Chemical's epoxy resin 1004K (softening point 97 ° C) with an as-one freezing and pulverizing machine TPH-01 and made of an epoxy resin and having an average particle size of 23 µm Got.

<Manufacture of primer composition (P-1)>
Asahi Clin (registered trademark) AC-6000 (boiling point: 114 ° C., KB value: 5) manufactured by Asahi Glass Co., Ltd. was used as dispersion medium-1. Reactive FR-1 was blended at a ratio of 100 parts by mass, EP at 10 parts by mass, and dispersion medium-1 at a ratio of 170 parts by mass and stirred to prepare a primer composition (P-1).
This primer composition produced a precipitate after 300 hours, but it was easily redispersed by turning upside down and the storage stability was good.

<Manufacture of laminates>
An aluminum substrate having a length of 100 mm, a width of 150 mm, and a thickness of 1 mm was used as a test substrate. The primer composition (P-1) was applied to the surface of the test substrate using an air spray gun for liquid paint (manufactured by Meiji Machinery Co., Ltd.), suspended in an oven and baked at 300 ° C. for 10 minutes. Then, a primer layer having a thickness of 33 μm was formed to obtain a substrate with a primer layer.
Next, the surface is electrostatically coated with a powder made of a non-reactive fluoropolymer for topcoat (Fluon (registered trademark) ETFE TL-081 manufactured by Asahi Glass Co., Ltd.) (non-reactive FR) at 300 ° C. By baking for 10 minutes and repeating this electrostatic coating and baking process four times, a top coat layer having a total thickness of 510 μm was formed, and a coating test piece was obtained. The initial peel strength of the topcoat layer was 78.7 N / cm, and sufficient peel strength was exhibited after the hot water resistance test and the alkali resistance test.

[Example 2] to [Example 6]
As shown in Table 1, by changing the type, blending, and heat treatment temperature of the powder comprising the reactive fluoropolymer and the adhesive resin, the primer composition (P-2) to the primer composition (P -6) was prepared, and a base material with a primer layer and a coating test piece were obtained. When the same evaluation as in Example 1 was performed, good results were obtained. Here, the powder made of the reactive fluoropolymer (reactive FR-2) changes the pulverization conditions of the powder made of the reactive fluoropolymer prepared in Example 1 (reactive FR-1). Obtained.

[Example 7]
A primer composition (P-7) was prepared with the formulation shown as Example 7 in Table 2 to obtain a substrate with a primer layer and a coating test piece. When the same evaluation as in Example 1 was performed, the peel strength was good.

[Example 8 (comparative example)]
A primer composition (P-8) was prepared with the formulation shown as Example 8 in Table 2 to obtain a substrate with a primer layer and a coating test piece. When the same evaluation as in Example 1 was performed, it was considered that no powder made of an adhesive resin was used, and thus the peel strength was low.

[Example 9 (comparative example)]
A primer composition (P-9) was prepared with the formulation shown as Example 9 in Table 2 to obtain a substrate with a primer layer and a coating test piece. When the same evaluation as in Example 1 was performed, it was considered that a powder made of a reactive fluoropolymer was not used, and thus the peel strength was low.

[Example 10 (comparative example)]
A primer composition (P-10) was prepared using CFC-113 having a low boiling point with the formulation shown as Example 10 in Table 2, and a substrate with a primer layer and a coating test piece were obtained. When the same evaluation as in Example 1 was performed, the storage stability and spraying workability of the primer composition were poor, and the peel strength, particularly the peel strength after the hot water resistance test and the alkali resistance test, was low.
[Example 11 (comparative example)]
A primer composition (P-11) prepared by dissolving a surfactant (Triton X-100) in water as a dispersion medium with the formulation shown as Example 11 in Table 2 was prepared. Materials and paint specimens were obtained. When the same evaluation as in Example 1 was performed, the storage stability of the primer composition was poor. Moreover, the primer layer was repelled and the appearance was poor. Further, the primer composition liquid was easy to foam and the workability was low.

Reactive FR-1: Reactive ETFE powder, average particle size 20 μm, true specific gravity = 1.78, MFR = 25 g / 10 minutes Reactive FR-2: Reactive ETFE powder, average particle size 10 μm, true specific gravity = 1.78, MFR = 25 g / 10 min Non-reactive FR: Asahi Glass Co., Ltd. full-on ETFE TL-081, average particle size 76 μm, true specific gravity = 1.74, MFR = 22 g / 10 min EP: Mitsubishi Chemical Corporation bisphenol type Epoxy resin powder, pulverized product of jER (registered trademark) 1004k, molecular weight 1,650, epoxy equivalent 925, softening point 97 ° C., average particle size 23 μm
PH: Phenoxy resin powder PKHP-200 manufactured by InChem, molecular weight 52,000, glass transition temperature 92 ° C., average particle size 28 μm
PES: polyethersulfone powder manufactured by Sumitomo Chemical Co., Sumika Excel (registered trademark) 4100P pulverized product, glass transition temperature 225 ° C., average particle diameter 21 μm
PA: Nylon 12 powder manufactured by Daicel Evonik, Best Ginto (registered trademark) 2070, melting point 175 to 180 ° C., average particle size 5 μm
PAI: Polyamideimide powder manufactured by Solvay Solexis, TORLON (registered trademark) 400TF, melting point 300 ° C., average particle size 35 μm
PPS: Toray polyphenylene sulfide powder, Trepearl (registered trademark) PPS, melting point 280 ° C., average particle size 30 μm
MC: Nissan Chemical Co. Melamine Cyanurate Powder, MC-6000, decomposition start temperature 200 ° C., average particle size 3 μm
Surfactant: Triton (registered trademark) X-100 (polyoxyethylene octyl phenyl ether) manufactured by Dow Chemical

Ozone depletion coefficient: Relative ratio when CFC-11 is set to 1 Global warming coefficient: Relative ratio when carbon dioxide is set to 1, 100 years

  The primer composition of the present invention is superior in adhesion to a substrate, excellent in storage stability, uniform coating properties and durability as compared with conventional primer compositions. The primer composition of the present invention can be applied to the surface of a heat-resistant substrate such as metal, glass and ceramics, and is useful as a primer for coating, lining and surface treatment with a fluoropolymer. The primer composition and coated article of the present invention include various containers, pipes, tubes, tanks, pipes, joints, rolls, autoclaves, heat exchangers, distillation towers, jigs, valves, stirring blades, tank trucks, pumps, blowers. Can be used for casings, centrifuges, cooking appliances, etc.

Claims (6)

  Reactive fluorine-containing polymer containing powder (X) made of reactive fluorine-containing polymer, powder (Y) made of adhesive resin, and fluorine-containing dispersion medium (Z) having a boiling point of 50 to 200 ° C. The content of the powder (Y) made of an adhesive resin is 1 to 30 parts by weight and the boiling point is 50 to 200 ° C. with respect to 100 parts by weight of the powder (X) made of a polymer ( The primer composition whose content of Z) is 20-500 mass.   The primer composition according to claim 1, wherein the fluorine-containing dispersion medium (Z) having a boiling point of 50 to 200 ° C is a hydrofluorocarbon or a hydrofluoroether having no chlorine atom in the molecule and a Kauributanol value of 30 or less. object.   Powder (Y) made of adhesive resin is powder made of epoxy resin, powder made of phenoxy resin, powder made of melamine cyanurate, powder made of polyethersulfone resin, powder made of polyamide resin, The primer composition according to claim 1 or 2, wherein the primer composition is one or more powders selected from the group consisting of a powder comprising a polyamideimide resin and a powder comprising a polyphenylene sulfide resin.   The powder (X) made of a reactive fluoropolymer is converted into a monomer having a repeating unit (A) based on tetrafluoroethylene, a repeating unit (B) based on ethylene, and an acid anhydride group and a polymerizable unsaturated bond. Based repeating unit (C2), (A) / (B) in a molar ratio of 20/80 to 80/20, and (C2) / ((A) + (B)) in a molar ratio of 1 / The primer composition according to any one of claims 1 to 3, wherein the primer composition is a powder comprising a 10,000 to 5/100 reactive ethylene / tetrafluoroethylene copolymer.   The laminated body by which the primer layer which is the heat processing thing of the primer composition of any one of Claims 1-4, and the topcoat layer which consists of a fluororesin were laminated | stacked in this order on the base-material surface.   The laminated body of Claim 5 whose peeling strength of the topcoat layer with respect to a base material is 40 N / cm or more.